"___ upon a time . . ." (4)

I believe the answer is:
(Other definitions for once that I've seen before include "Formerly; as soon as" , "... upon a time for the storyteller" , "Formerly - not repeated" , "At some time past" , "in bygone era" .)
I believe the answer is:
(Other definitions for once that I've seen before include "Formerly; as soon as" , "... upon a time for the storyteller" , "Formerly - not repeated" , "At some time past" , "in bygone era" .)